Rare Diseases of the Pancreas: Benign Pancreatic Cysts (Adenomas)

Benign pancreatic cysts, also known as adenomas, are abnormal tissue growths. Unlike malignant growths, pancreatic cysts do not invade surrounding tissue, nor do they metastasize and spread to other organs. Although a small percentage of benign growths eventually become malignant, most are harmless, and do not require treatment unless symptoms develop.

 

Benign pancreatic neoplasms are very rare diseases, accounting for only one to two percent of all pancreatic tumors. Malignant adenocarcinomas are, unfortunately, much more common, accounting for 95 percent of all cases.

Pancreatic pseudocysts are caused by repeated attacks of pancreatitis (inflammation of the pancreas). A pseudocyst is an accumulation of fluid surrounded by scar tissue resulting from pancreatitis. Pseudocysts are not tumors, and usually do not require treatment.

A serous cystadenoma is one of the more common forms of benign pancreas neoplasms. Although serous cystadenomas can obstruct digestive bile ducts, they do so only rarely, and are almost always non-cancerous. The growths are more common in women than in men: as many as 66 percent of all cases occur in women. They average between five and eight centimeters in length at the time of diagnosis, although growths as large as twenty centimeters have been reported.

 

Symptoms, when they occur, are usually non-specific. Abdominal pain, nausea, and vomiting have been reported. One quarter of all patients with serous cystadenoma report no symptoms at all.

Mucinous cystic tumors account for up to fifty percent of pancreatic cysts. Some mucinous neoplasms are malignant. Some are benign but may become malignant. As such, a mucinous cyst is often surgically removed, whether biopsy results indicate it is malignant, or not. Women are more susceptible to mucinous cystic tumors than men, and account for eighty percent of cases.

 

Although CT scans, MRIs and other diagnostic tools may provide clues about the nature of a pancreatic neoplasm, analysis of the cystic fluid is the best way to distinguish between the different growths. Fluid may be gathered through an endoscope, or by inserting a long, thin needle into the growth and aspirating (withdrawing) a sample.